Mexico Suspends U.S. Livestock Imports Over Screwworm Detection

Mexico suspended imports of live cattle, sheep, goats, pigs, and other animals from the United States starting June 9, 2026, after confirming five cases of screwworm (gusano barrenador) in U.S. territory.

The measure was agreed upon by Mexico's Ministry of Agriculture and Rural Development through its National Service for Agricultural Health, Safety and Quality (Senasica), in coordination with the USDA's Animal and Plant Health Inspection Service (APHIS). According to El Financiero, confirmed cases were identified in La Salle, Gillespie, and Zavala counties in Texas, plus one case in a dog in New Mexico. The quarantine aims to protect Baja California, Baja California Sur, Chihuahua, and Sinaloa, the cattle-ranching states of northwest Mexico that currently remain free of the pest.

What is Screwworm?

Screwworm is caused by a parasitic fly that infects warm-blooded animals. Mexico successfully eradicated the pest in the 1960s. The standard containment technique involves raising flies in laboratory conditions, sterilizing males through radiation, and releasing them to prevent viable reproduction. The import suspension covers five livestock categories and extends to songbirds and ferrets from the United States. Senasica received initial notification on June 4 following detection of the outbreak in Zavala County.

Quarantine to Remain Until Further Notice

The sanitary border will stay closed until APHIS-USDA demonstrates control over the outbreak. The next status report between both agencies in coming weeks will determine whether the measure continues or is adjusted.

Frequently Asked Questions

**Why did Mexico suspend livestock imports from the U.S. in June 2026?**

Mexico suspended live animal imports from the United States starting June 9, 2026, after confirmation of five screwworm cases in Texas and New Mexico. This was a precautionary health measure implemented by Mexico's Ministry of Agriculture and Senasica.

**Which animals are covered by the import suspension?**

The suspension covers cattle, ruminants, sheep, goats, pigs, songbirds, and ferrets from the United States, under the agreement between Senasica and APHIS-USDA announced June 4, 2026.

**Which Mexican states does the quarantine protect?**

The sanitary barrier aims to preserve screwworm-free status in Baja California, Baja California Sur, Chihuahua, and Sinaloa, the primary livestock-producing regions of northwest Mexico.

Sources